Latanoprost increases the severity and recurrence of herpetic keratitis inthe rabbit

PURPOSE: To determine whether topically applied latanoprost increases the s everity of acute herpes simplex keratitis, the rate of recurrence of herpes keratitis, or both, in the rabbit. METHODS: To determine the effect on severity of acute herpetic keratitis, t he corneas of New Zealand white rabbits were infected with either the less- corticosteroid sensitive McKrae strain or the corticosteroid-sensitive F(MP )E strain of herpes simplex virus type 1. Rabbits were randomly assigned to twice-a-day treatment with latanoprost 0.005%, dexamethasone sodium phosph ate 0.1%, or balanced saline solution within 3 days of infection and evalua ted daily for up to 13 days after infection. The severity of keratitis was graded in a masked manner. To determine the effect on recurrences of herpet ic keratitis, animals infected with McKrae strain herpes simplex virus type I that survived to day 32 after infection were randomized to treatment wit h latanoprost 0.005% or balanced saline solution and evaluated for the pres ence of corneal lesions from postinfection day 32 to day 47. RESULTS: In the severity studies, treatment of F(MP)E-infected corneas with latanoprost or dexamethasone significantly worsened herpetic keratitis; by postinfection day 5, F(MP)E-infected eyes treated with dexamethasone or la tanoprost demonstrated significantly higher severity scores than the eyes t reated with balanced saline solution (P = .0001 and .008, respectively). Sc ores of McKrae-infected corneas treated with latanoprost or dexamethasone w ere not significantly different from scores of balanced saline solution-tre ated corneas, In the recurrence study, treatment with latanoprost significa ntly increased the appearance of clinical recurrences in McKrae-infected ey es, compared with balanced saline solution treatment (P = .0064). CONCLUSION: Latanoprost may worsen acute herpetic keratitis in the rabbit e ye and increase the risk of recurrences in latently infected animals. (C) 1 999 by Elsevier Science Inc. All rights reserved.